Grounding clamp



L. G. WILDER GROUNDING CLAMP Filed May 5, 1939 4 INVENTOR ATTORNEY Patented Aug. 13, 1940 UNITED STATES ATENT OFFICE GROUNDING CLAMP Leon G. Wilder, Elmira, N. Y.

Application May 5, 1939, Serial No. 271,850

Claims. (Cl. 173-273) This invention relates to a grounding clamp Figure 9 is a view similar to Figure 7, but show- Which is especially useful in connection with are ing a still further modified form of gripping welding, although not limited to this particular member.

use. Figure shows a further modified construc- In arc welding, in many cases, it is necessary, tion. to carry a pair of leads from the welding machine Figure 11 is a view on the line lll| of Figto the work on which the welding operation is ure 1. to be performed. By way of example, but not The clamp is made up of two elongated memof limitation, in welding an automotive vehicle hers I and 2 which, in the form shown in Figures 1 0 frame one of the wires from the welding machine 1 and 7, have the greater portion of their length 1 is attached to the Welding handle carrying the L-shaped, with gripping surfaces 3 and 4 where welding rod, while the other must be attached the two pieces meet when there is no object beto some part of the frame of the vehicle, and to tween them. The upper end of the grip or memexpedite this particular kind of work I have deher 2 has fastened thereto a stud 5. One end of veloped the clamp to be hereinafter illustrated the d 5 is ded at 5 d y be SCTeWed 15 and described. into the grip 2 and then fastened in place by a It is therefore the principal object of my inlook washer, if desirable, and a nut l which will vention to provide a grounding clamp which is s draw the shoulder 8 of the stud against an inner constructed that it may be quickly applied to a WeVe a ShOWn in Figure the face some exposed part of the work-piece or structure, 9 is recessed to receive a p y n lly p d rod 20 the device being adaptable to various forms and 5 therein to p ve t t from u g in the g l shapes. 2 and its collar l2.

Another object of my invention is to provide a An electrical conductor [9 is adapted to be fasgrounding clamp which has ahigh current-carrytened to the threaded end 6 of the stud 5, as by ing capacity with extremely small electrical a u 1- The rod 5 e te u h e ppe 2o losses therein. At the same time, it is an object end of the p l d a through a tubu ar of my invention to provide a, grounding clamp member H which may be Of any suitable matewhich is very sturdy and rigid in its construction, rial, Steel being Preferable e member I I iS and on whi h ill ta d tr m d amount fastened in any satisfactory manner to .a. collar of abuse i i 7 portion l2 which extends outwardly from the grip 13;)

Thes and oth objects i l be apparent t I. The outer or free end of the stud 5 is threadone skilled in this art from a study of the specified at to receive an elongatedmlt Which y cation taken in connection with the annexed be threaded y for a p Of its length to dmwihg, wherein; gage the threaded portion I3 on the stud 5. P0-

Figure 1 perspective View of t assemmed sitioned around the rod 5 within the tube H is form of my device, one portion being broken away a Spring l5 Which is adapted t0 be engaged y the t Show t interior construction inner end of the nut [4, whereby tension is ap- Figure 2 is an elevational view of Figure 1 lookplied to the Spring I5 50 as t p ss the ame ihg from left t right t View being Substanand force the gripping member I into clamping 4.0 tially full-size of a device which I have found engagement with any Object to which the device so to be very practical in use. is pp d- Figure 3 is a view similar to Figure 2, b t of The application of the device will be obvious the opposite side of the device shown in Figure 1. from the preceding description- TO apply the Figure 4 is a view on the line l l of Figure 1. clamp to any piece o Work for example to an Figure 5 is a perspective view of the upper end u the grip pulled awafy from the of one of the clamping members, about on the grip 2 against h tensmn of the sprmg so as line of Figure 1. to allow the grips l and 2 to be passed over Figure 6 is a perspective view of the clamping zfiggi zifi f g z gg ggg ifg ggi g rod used holdmg the Clampmg or 'grlppmg the bumper, contact being made along the length 50 members l h of the grips I and 2 on the surfaces 3 and 4, it

Ffgure 7 w on f lme of Flgure being understood that the grips l and 2 are made Flgure 8 1S VleW slmllal' t0 Flame 7, but out of satisfactory material, such as a suitable showing a modified form of construction of the grade of b 5 gripping members. It will be noted that the grips I and 2 are Gil made exactly alike so that only one mold is required for making the device. It will also be noted that the outer end of the nut 54 is knurled at R6 to assist in screwing the nut ofi and on the threaded potion of the stud 5. Also, as shown in Figure 1 and 11, the axial center line of the stud is 01f the axial center of the tubular member i I, so that when the nut M is in place on the stud, it engages a portion of the surface of the tube I i. The idea of this construction is that the upward pressure on the nut M, due to its engagement with the lower part of the Wall of the tube H, is such as to tend to tilt the threaded end of the stud 5 upwardly, which will draw the lower end of the grip 2 toward the grip I, the idea being to overcome any tendency of the lower end of the grip members i and 2 from undue spreading.

While this particular detail construction is not actually necessary, it has some advantage. However, it will be understood that the stud 5, which is polygonal in shape, a square form being indicated, preferably has a close fit with the member I. It will also be noted that the upper ends of the grips I and 2, wherein the stud E5 is positioned, are solid with the exception of a hole through which the stud passes, and a small area ll adjacent the upper part of the gripping surfaces 3 and l.

Instead of making the grips l and 2 below the reenforced surfaces 9 in the form shown in Figure '7, they may be made oval in shape, as shown in Figure 8, or circular as shown in Figure 9; and in some cases, they may be substantially solid, with the exception of a central hole I8, as shown in Figure 10.

In arc welding, the size of the ground wire is usually not smaller than a #1 cable, and the hole 58 is made somewhat smaller than this so that the wire may be inserted longitudinally in the hole instead of cross-wise, as in the construction shown in Figures 7, 8 and 9. By adjusting the nut M and pulling the grips i and 2 apart, the clamp will automatically grip pieces of various thicknesses and shapes, the particular clamp from which the drawings of this application were made, being capable of adjustment to take in pieces up to approximately three inches in thickness.

While I have shown an elongated nut M, a :1 put and a cooperating collar may be used in i. .s place, certain of the other details may be varied to some extent, without departing from the spirit of my invention or the scope of the appended claims.

What I claim is:

l. A grounding clamp comprising, a pair of elongated metallic grips having diametrically and oppositely disposed gripping surfaces along substantially their full length, a tubular member laterally and rigidly carried by one of said grips at one end thereof, a single stud threaded at both ends carried by ie other of said grips at one end and extending through it, as well as through the end of the grip carrying the tubular member and through at least the greater part of the length of the tubular member, a spring disposed within the tubular member and a nut on the end of the stud going into the tubular member, and having a part at least adapted to enter the tubular member to compress said spring, as and for the purpose described, and means on the other threaded end of the stud for attaching an electrical conductor to the stud.

2. A grounding clamp comprising, a pair of elongated metallic grips having diametrically and oppositely disposed gripping surfaces along substantially their full length, a tubular member laterally and rigidly carried by one of said grips at one end thereof, a single stud threaded at both ends carried by the other of said grips at one end and extending through it, as well as through the end of the grip carrying the tubular member and through the tubular member, a spring disposed within the member around the stud and a nut on the tubular end of the stud going into the tubular member and having a part at least adapted to enter the tubular member to compress said spring, the stud being positioned within the tubular member with its axis oif the axial center of said tubular member forcing the said nut on the stud into engagement with a part of the wall of the tubular member for the purpose described.

3. A grounding clamp including a pair of metallic grips having gripping surfaces for the greater part of their length, a tubular member fastened to one grip and extending laterally therefrom, a stud fastened to the other grip and having means for connecting an electrical conductor thereto, the stud extending through at least the greater portion of the length of the tubular member or" the first-mentioned grip, the free end of the stud being threaded, a spring within the tubular member and a nut on the threaded end of the stud adapted to apply tension to the spring for the purpose described, the grips being separable by lateral displacement, one from the other, throughout their entire length, the grips and stud being provided with cooperative means for holding the grips in non-turnable position.

4. A grounding clamp including a pair of elongated metal pieces having diametrically disposed gripping surfaces along the greater part of their length, a tube fastened at the end of one piece and extending laterally away from it, a spring within the tube, a stud fastened to an end of the other piece and provided with means for attaching an electrical conductor thereto, the stud extending through the tube end of the other piece and through the spring and tube, this free end of the stud being threaded and an elongated nut on this threaded end of the stud adapted to extend within the tube to compress said spring for the purpose described.

5. A grounding clamp as set forth in claim 4, further characterized in that the stud is positioned within the tube with its axis off the axial center of said tubular member forcing the nut end entering the tube into engagement with a portion of the inner surface of the tube for the purpose described.

LEON G. WILDER.

CERTIFICATE OF CORRECTION.

Patent No. 2,211,L 51. August 15, 191m.

LEON G. WILDER. It is hereby certified that error appears in the I printed specification of the above numbered patent requiring correction as follows: Page 2, second co1mnn, line 19, claim 2, strike out theword "tubular" first occurrence,

and insert the same before "member" in line 18, same claim; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office;

Signed and sealed this 8th day of October, A. D. 1911.0.

Henry Van Arsdale, (Seal) Acting Commissioner of Patents. 

